I went to the my local yacht riggers and gave them the length I needed. I got a length of wire wit a fork at one end and a bottle screw and fork at the other, I shacled one end to the light bar and the other to an eye bolt on the wing. It was never a problem with the MOT, but I have since removed them. Quick and easy to refit when I need to go back into the woods.
Google yacht riggers some one like The Rig Shop could make these up pretty quickly.
Ruari